From b38e468429d08f26cb0e775fc32da8131cd7ec1f Mon Sep 17 00:00:00 2001
From: pjpuzzler <31143551+pjpuzzler@users.noreply.github.com>
Date: Sat, 12 Aug 2023 14:19:01 -0400
Subject: [PATCH] Fixed generate_castling_moves to_mask bug

---
 chess/__init__.py | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/chess/__init__.py b/chess/__init__.py
index 65719fd5c..3c357f578 100644
--- a/chess/__init__.py
+++ b/chess/__init__.py
@@ -3610,11 +3610,13 @@ def generate_castling_moves(self, from_mask: Bitboard = BB_ALL, to_mask: Bitboar
         bb_f = BB_FILE_F & backrank
         bb_g = BB_FILE_G & backrank
 
-        for candidate in scan_reversed(self.clean_castling_rights() & backrank & to_mask):
+        for candidate in scan_reversed(self.clean_castling_rights() & backrank):
             rook = BB_SQUARES[candidate]
 
             a_side = rook < king
             king_to = bb_c if a_side else bb_g
+            if not king_to & to_mask:
+                continue
             rook_to = bb_d if a_side else bb_f
 
             king_path = between(msb(king), msb(king_to))